Aim: To develop and perform an initial validation of a score to measure severity of illness in hospitalized children with severe acute malnutrition (SAM).

Methods: A prospective study enrolled SAM children aged 6-59 months hospitalized in Borno State, Nigeria. Candidate items associated with inpatient mortality were combined and evaluated as candidate scores. Clinical and statistical methods were used to identify a preferred score.

Results: The 513 children enrolled had a mean age of 15.6 months of whom 48 (9%) died. Seven of the ten evaluated items were significantly associated with mortality. Five different candidate scores were tested. The final score, Responses to Illness Severity Quantification (RISQ), included 7 items: heart rate, respiratory rate, respiratory effort, oxygen saturation, oxygen delivery, temperature and level of consciousness. The mean RISQ score on admission was 2.6 in hospital survivors and 7.3 for children dying <48hr. RISQ scores <24hr before death had an area under the receiver operating characteristic curve (AUROC) of 0.93. The RISQ score performed similarly across differing clinical conditions with AUROCs 0.77-0.98 for all conditions except oedema.

Conclusion: The RISQ score can identify high risk malnourished children at and during hospital admission. Clinical application may help prioritize care and potentially improve survival.